In recent years, with the rapid development of technology, mobile products with biometric recognition functions have gradually come into people's life and work, and fingerprint technology has received much attention owing to the unique identity of fingerprint.
In related art, light of different intensities can be converted into photocurrents of different magnitudes using photosensitive devices. Thus, owing to the difference between valleys and ridges of the fingerprint, reflected light of different intensities can be generated when a finger is irradiated by a light source. Thereby different photocurrents can be generated. On this basis, fingerprint patterns can be obtained.